Methylene chloride is a widely used component for paint stripping products. Three major categories of use include industrial use, professional use (i.e., by a tradesman), and consumer use. Methylene chloride is highly volatile and the primary route of exposure is inhalation, which can lead to acute and chronic human health hazards. For example, methylene chloride can cause acute and chronic effects on the central nervous system. The inhalation of methylene chloride can result in short term effects such as dizziness, clumsiness, headache, nausea, and numbness of fingers and toes, and long term effects such as loss of concentration, memory loss, and personality changes. There have been numerous occupational and consumer deaths during paint stripping operations resulting from acute methylene chloride poisoning. Further, methylene chloride is classified as a human carcinogen. Consequently, there is increasing demand for paint stripping products that do not contain methylene chloride.
Several commercially available products do not contain methylene chloride, however, their paint stripping performance is significantly below that of methylene chloride, and the replacement chemicals, such as N-Methyl-2-Pyrrolidone (NMP), introduce other environmental, health, and safety hazards. Additionally, there are practical considerations surrounding the use of stripping products that do not include methylene chloride, for example, longer required dwell times, and stripping coatings one layer at a time necessitating multiple applications.
Accordingly, there remains a continuing need for alternative compositions for removing various multilayer coatings from surfaces (e.g., paint stripping compositions) that do not contain methylene chloride, NMP, or other hazardous ingredients. An alternative composition preferably can have a low volatile organic compound (VOC) content, be effective across a wide range of coatings and surfaces with a reasonable dwell time, does not damage substrate material (i.e., will not stain, discolor, or alter the substrate, corrode a metal substrate, or raise the wood grain for wood surfaces), and have adequate viscosity to remain in place on vertical surfaces. Effective paint stripping compositions can further exhibit adequate penetration into the coating to reach the substrate surface, and can have desirable Hansen Solubility Parameters in order to dissolve the variety of coatings that can be encountered.